Long-Term Outcomes of Patients with Hydrocephalus Secondary to Tectal Plate Glioma versus Idiopathic Aqueductal Stenosis: Results from a Single Center

INTRODUCTION

Tectal plate gliomas (TPG) constitute a distinct entity of benign tumors of the brain stem which show an indolent clinical course. Adequate treatment of secondary hydrocephalus is undoubtedly a major factor in the outcome. However, little is known about to what degree the tumor itself determines the long-term outcome of these patients.

METHODS

We retrospectively analyzed and compared the clinical and radiological data of 16 pediatric TPG patients with data of 12 pediatric idiopathic aqueductal stenosis (IAS) patients treated in our center from 1988 to 2018. For both groups, we assessed the long-term outcome in terms of hydrocephalus management, and for the TPG group, we assessed tumor growth during follow-up. In a separate prospective part of the study, we performed a neuropsychological evaluation in a subgroup of patients using a standardized testing battery, covering intelligence, learning, memory, executive functions, and an inventory on depression.

RESULTS

In the TPG group, the mean clinical and radiological follow-up was 84 and 70 months, respectively. On average, the maximum diameter of the tumor increased by 11% (p = 0.031) and the estimated tumor volume with 35% (p = 0.026) on radiological follow-up. The fronto-occipital horn ratio (FOHR) decreased by 23% on average after treatment. In the IAS group, the mean clinical and radiological follow-up was 117 and 85 months, respectively. In this group, the FOHR decreased by 21% on average. Neurocognitive testing revealed significant higher scores in the TPG group on global intelligence (TPG = 109, IAS = 85.5, U = 3, p < 0.01, z = -2.71), performance (TPG= 100, IAS = 85, U = 7, p = 0.03, z = -2.2), and verbal intelligence (TPG = 122, IAS = 91.5, U = 2, p < 0.00, z = -2.87) as well as working memory (TPG = 109.5, IAS = 77, U = 0.5, p = 0.01, z = -2.46).

CONCLUSION

Our results suggest that the long-term outcome in TPG patients is acceptable and that cognition is substantially better preserved than in patients with IAS. This puts the idea of a significant contribution of the tumoral mass to disease outcome on the long term in question. Adequate and prompt management of hydrocephalus is the most important factor in long-term cognitive outcome.

Long-Term Reliability of Neuroendoscopic Aqueductoplasty in Idiopathic Aqueductal Stenosis-Related Hydrocephalus

BACKGROUND

During the 1990s, endoscopic aqueductoplasty (AP) was considered to be a valuable alternative to endoscopic third ventriculostomy (ETV) in treating hydrocephalus related to idiopathic aqueductal stenosis (iAS), with promising short-term outcomes.

OBJECTIVE

To evaluate the long-term outcome of AP in the treatment of iAS.

METHODS

Long-term follow-up clinical examinations and magnetic resonance (MR) imaging were performed for patients treated by an AP for iAS in our department.

RESULTS

Twenty patients (14 female, 6 male, mean age 41.7 yr, range 0.5-67 yr) were treated between 1996 and 2002. Two patients were lost to long-term follow-up. One patient died 6 mo after AP, but death was not related to the procedure. The mean follow-up for the remaining 17 patients was 120 mo. Clinically relevant aqueductal reclosure was observed in 11/17 patients after a mean follow-up of 53.4 mo. These 11 patients underwent ETV, which has been successful during further follow-up. Four of the six remaining patients presented with no clinical symptoms, although aqueductal restenosis was observed on MR imaging. Thus, the overall failure rate of AP was 88.2%. The failures were homogeneously distributed over the entire follow-up period.

CONCLUSION

AP has a high risk of failure during long-term follow-up and is not recommended as the first choice of treatment in hydrocephalus caused by iAS. ETV should be done instead. AP may be reserved for a limited number of patients in whom ETV is not feasible but should be combined with stenting to avoid reclosure of the aqueduct.